Estrogen receptor-beta in quail: Cloning, tissue expression and neuroanatomical distribution

A partial estrogen receptor-beta (ER beta) cDNA had been previously cloned and sequenced in Japanese quail, The 3'- and 5'-rapid amplification of cDNA ends techniques were used here to identify a cDNA sequence of the quail ER P that contains a complete open reading frame. For the first time in an avi an species, this cDNA sequence and the corresponding amino acid sequence ar e described, They are compared with the known ER beta sequences previously described in mammals and with the ER alpha sequences identified in a select ion of mammalian and avian species. The analysis by Northern blotting of th e ER beta mRNA expression in the brain and kidneys revealed the presence of several transcripts. The presence of ER beta identified by reverse transcr iptase-polymerase chain reaction demonstrated a widespread distribution qui te different from the distribution of ER alpha. The complete neuroanatomica l distribution of ER beta mRNA as determined by in situ hybridization with S-35- and P-33-labeled oligoprobes is also presented. Transcripts are prese nt in many nuclei implicated in the control of reproduction such as the med ial preoptic nucleus, the nucleus striae terminalis, and the nucleus taenia e, the avian homologue of the amygdala, These data demonstrate the presence of ER beta in a nonmammalian species and indicate that the (neuro)anatomic al distribution of this receptor type has been conserved in these two class es of vertebrates, The role of this receptor in the control of reproduction and other physiological processes should now be investigated. (C) 1999 Joh n Wiley & Sons, Inc. J Neurobiol 40: 327-342, 1999.